U.S. patent application number 17/053061 was filed with the patent office on 2021-07-29 for low-dose imaging method and apparatus.
The applicant listed for this patent is OUR UNITED CORPORATION, SHENZHEN OUR NEW MEDICAL TECHNOLOGIES DEVELOPMENT CO., LTD.. Invention is credited to Jinsheng LI, Jiuliang LI, Yingwen WU, Hao Yan.
Application Number | 20210233293 17/053061 |
Document ID | / |
Family ID | 1000005569333 |
Filed Date | 2021-07-29 |
United States Patent
Application |
20210233293 |
Kind Code |
A1 |
Yan; Hao ; et al. |
July 29, 2021 |
LOW-DOSE IMAGING METHOD AND APPARATUS
Abstract
Provided is a low-dose imaging method, including continuously
acquiring projection data; generating a first image by processing
the acquired projection data before a data volume of the acquired
projection data reaches a preset volume, and displaying the first
image; and generating a second image by processing the preset
volume of projection data when the data volume of the acquired
projection data reaches the preset volume, and displaying the
second image.
Inventors: |
Yan; Hao; (Xi'an City,
Shaanxi, CN) ; LI; Jiuliang; (Xi'an City, Shaanxi,
CN) ; WU; Yingwen; (Xi'an City, Shaanxi, CN) ;
LI; Jinsheng; (Shenzhen City, Guangdong, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
OUR UNITED CORPORATION
SHENZHEN OUR NEW MEDICAL TECHNOLOGIES DEVELOPMENT CO.,
LTD. |
Xi'an City, Shaanxi
Shenzhen City, Guangdong |
|
CN
CN |
|
|
Family ID: |
1000005569333 |
Appl. No.: |
17/053061 |
Filed: |
May 4, 2018 |
PCT Filed: |
May 4, 2018 |
PCT NO: |
PCT/CN2018/085628 |
371 Date: |
November 4, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01T 1/17 20130101; G06T
11/008 20130101; G06T 2211/424 20130101; G06T 11/006 20130101 |
International
Class: |
G06T 11/00 20060101
G06T011/00; G01T 1/17 20060101 G01T001/17 |
Claims
1. A low-dose imaging method, comprising: continuously acquiring
projection data; generating a first image by processing the
acquired projection data before a data volume of the acquired
projection data reaches a preset volume, and displaying the first
image; and generating a second image by processing the preset
volume of the projection data in response to the data volume of the
acquired projection data reaching the preset volume, and displaying
the second image.
2. The method according to claim 1, wherein said generating the
second image by said processing the preset volume of the projection
data, and said displaying the second image comprise: generating an
i.sup.th iteratively reconstructed image by performing an i.sup.th
iterative reconstruction operation in an iterative reconstruction
on the preset volume of the projection data; and displaying the
i.sup.th iteratively reconstructed image, wherein i is at least one
of 1, 2, . . . , or m, m being a total number of iterative
reconstruction operations in the iterative reconstruction, and an
integer greater than or equal to 1.
3. The method according to claim 2, wherein said displaying the
i.sup.th iteratively reconstructed image comprises: displaying the
i.sup.th iteratively reconstructed image and progress information
of generating an m.sup.th iteratively reconstructed image.
4. The method according to claim 1, wherein said generating the
second image by said processing the preset volume of the projection
data, and said displaying the second image comprise: generating an
i.sup.th iteratively reconstructed image by performing an i.sup.th
iterative reconstruction operation in an iterative reconstruction
on the preset volume of the projection data; generating an i.sup.th
fused image by fusing the i.sup.th iteratively reconstructed image
and the first image, and displaying the i.sup.th fused image,
wherein i is at least one of 1, 2, . . . , or m-1, m being a total
number of iterative reconstruction operations in the iterative
reconstruction, and an integer greater than or equal to 2; and
generating an m.sup.th iteratively reconstructed image by
performing an m.sup.th iterative reconstruction operation in the
iterative reconstruction on the preset volume of the projection
data, and displaying the m.sup.th iteratively reconstructed
image.
5. The method according to claim 4, wherein said generating the
i.sup.th fused image by said fusing the i.sup.th iteratively
reconstructed image and the first image comprises: determining a
weight of a pixel value in the i.sup.th iteratively reconstructed
image and a weight of a pixel value in the first image according to
a number i of the iterative reconstruction operations; and
generating the i.sup.th fused image by fusing the i.sup.th
iteratively reconstructed image and the first image according to
the weight of the pixel value in the i.sup.th iteratively
reconstructed image and the weight of the pixel value in the first
image.
6. The method according to claim 5, wherein said displaying the
i.sup.th fused image comprises: displaying the i.sup.th fused image
and progress information of said generating the m.sup.th
iteratively reconstructed image.
7. The method according to claim 1, wherein said displaying the
second image comprises: displaying the second image and quality
information of the second image, wherein the quality information is
indicative of image quality of the second image relative to the
first image.
8. (canceled)
9. A low-dose imaging apparatus, comprising: a memory, a processor,
and a computer program stored in the memory and executable by the
processor, wherein the computer program, when executed by the
processor, causes the processor to perform a low-dose imaging
method comprising: continuously acquiring projection data;
generating a first image by processing the acquired projection data
before a data volume of the acquired projection data reaches a
preset volume, and displaying the first image; and generating a
second image by processing the preset volume of the projection data
in response to the data volume of the acquired projection data
reaching the preset volume, and displaying the second image.
10. A non-volatile computer-readable storage medium storing a
computer program thereon, wherein the computer program, when
executed by a processor, causes the processor to perform a low-dose
imaging method comprising: continuously acquiring projection data;
generating a first image by processing the acquired projection data
before a data volume of the acquired projection data reaches a
preset volume, and displaying the first image; and generating a
second image by processing the preset volume of the projection data
in response to the data volume of the acquired projection data
reaching the preset volume, and displaying the second image.
11. The storage medium according to claim 10, wherein said
generating the second image by said processing the preset volume of
the projection data, and said displaying the second image comprise:
generating an i.sup.th iteratively reconstructed image by
performing an i.sup.th iterative reconstruction operation in an
iterative reconstruction on the preset volume of the projection
data; and displaying the i.sup.th iteratively reconstructed image,
wherein i is at least one of 1, 2, . . . , or m, m being a total
number of iterative reconstruction operations in the iterative
reconstruction, and an integer greater than or equal to 1.
12. The storage medium according to claim 10, wherein said
generating the second image by said processing the preset volume of
the projection data, and said displaying the second image comprise:
generating an i.sup.th iteratively reconstructed image by
performing an i.sup.th iterative reconstruction operation in an
iterative reconstruction on the preset volume of the projection
data; generating an i.sup.th fused image by fusing the i.sup.th
iteratively reconstructed image and the first image, and displaying
the i.sup.th fused image, wherein i is at least one of 1, 2, . . .
, or m-1, m being a total number of iterative reconstruction
operations in the iterative reconstruction, and an integer greater
than or equal to 2; and generating an m.sup.th iteratively
reconstructed image by performing an m.sup.th iterative
reconstruction operation in the iterative reconstruction on the
preset volume of the projection data, and displaying the m.sup.th
iteratively reconstructed image.
13. A computer program product storing instructions thereon,
wherein the instructions, when executed by a computer, causes the
computer to perform the low-dose imaging method as defined in claim
1.
14. A chip, comprising a programmable logic circuit, wherein the
chip, when executed, is caused to perform the low-dose imaging
method as defined in claim 1.
15. A chip, comprising program instructions, wherein the chip, when
executed, is caused to perform the low-dose imaging method as
defined in claim 1.
16. The apparatus according to claim 9, wherein said generating the
second image by said processing the preset volume of the projection
data, and said displaying the second image comprise: generating an
i.sup.th iteratively reconstructed image by performing an i.sup.th
iterative reconstruction operation in an iterative reconstruction
on the preset volume of the projection data; and displaying the
i.sup.th iteratively reconstructed image, wherein i is at least one
of 1, 2, . . . , or m, m being a total number of iterative
reconstruction operations in the iterative reconstruction, and an
integer greater than or equal to 1.
17. The apparatus according to claim 16, wherein said displaying
the i.sup.th iteratively reconstructed image comprises: displaying
the i.sup.th iteratively reconstructed image and progress
information of generating an m.sup.th iteratively reconstructed
image.
18. The apparatus according to claim 9, wherein said generating the
second image by said processing the preset volume of the projection
data, and said displaying the second image comprise: generating an
i.sup.th iteratively reconstructed image by performing an i.sup.th
iterative reconstruction operation in an iterative reconstruction
on the preset volume of the projection data; generating an i.sup.th
fused image by fusing the i.sup.th iteratively reconstructed image
and the first image, and displaying the i.sup.th fused image,
wherein i is at least one of 1, 2, . . . , or m-1, m being a total
number of iterative reconstruction operations in the iterative
reconstruction, and an integer greater than or equal to 2; and
generating an m.sup.th iteratively reconstructed image by
performing an m.sup.th iterative reconstruction operation in the
iterative reconstruction on the preset volume of the projection
data, and displaying the m.sup.th iteratively reconstructed
image.
19. The apparatus according to claim 18, wherein said generating
the i.sup.th fused image by said fusing the i.sup.th iteratively
reconstructed image and the first image comprises: determining a
weight of a pixel value in the i.sup.th iteratively reconstructed
image and a weight of a pixel value in the first image according to
a number i of the iterative reconstruction operations; and
generating the i.sup.th fused image by fusing the i.sup.th
iteratively reconstructed image and the first image according to
the weight of the pixel value in the i.sup.th iteratively
reconstructed image and the weight of the pixel value in the first
image.
20. The apparatus according to claim 19, wherein said displaying
the i.sup.th fused image comprises: displaying the i.sup.th fused
image and progress information of said generating the m.sup.th
iteratively reconstructed image.
21. The apparatus according to claim 9, wherein said displaying the
second image comprises: displaying the second image and quality
information of the second image, wherein the quality information is
indicative of image quality of the second image relative to the
first image.
Description
[0001] The present disclosure is a national phase application based
on PCT/CN2018/085628, filed on May 4, 2018, the contents of which
are incorporated herein by reference in their entireties.
TECHNICAL FIELD
[0002] The present disclosure relates to the field of image
processing, and in particular, to a low-dose imaging method and
apparatus.
BACKGROUND
[0003] In clinical and medical imaging diagnosis and radiotherapy,
an X-ray computed tomography (CT) technology for diagnosis and a
core beam (CB) CT technology for radiotherapy or surgery guidance
have been widely applied. However, the excessive X-ray radiation
dose during CT and CBCT scanning has impacts on the health of a
patient. In order to reduce such adverse impacts, it is possible to
reduce the imaging radiation dose to the imaged object while the
imaging quality is ensured, data generated by X-ray after passing
through a target area of the patient is then captured as projection
data, and a target image for clinical treatment is obtained based
on the projection data. This mode is also referred to as a low-dose
imaging mode. In the low-dose imaging mode, one frame of projection
data is acquired each time the radiation is performed.
SUMMARY
[0004] Embodiments of the present disclosure provide a low-dose
imaging method and apparatus.
[0005] According to a first aspect, a low-dose imaging method is
provided. The method includes: continuously acquiring projection
data; generating a first image by processing the acquired
projection data before a data volume of the acquired projection
data reaches a preset volume, and displaying the first image; and
generating a second image by processing the preset volume of
projection data when the data volume of the acquired projection
data reaches the preset volume, and displaying the second
image.
[0006] Optionally, generating the second image by processing the
preset volume of projection data, and displaying the second image
includes: generating an i.sup.th iteratively reconstructed image by
performing an i.sup.th iterative reconstruction operation in
iterative reconstruction on the preset volume of projection data;
and displaying the i.sup.th iteratively reconstructed image;
wherein i is 1, 2, . . . , m, m being the total number of iterative
reconstruction operations in the iterative reconstruction, and m
being an integer greater than or equal to 1.
[0007] Optionally, displaying the i.sup.th iteratively
reconstructed image includes displaying the i.sup.th iteratively
reconstructed image and progress information of generating an
m.sup.th iteratively reconstructed image.
[0008] Optionally, generating the second image by processing the
preset volume of projection data, and displaying the second image
includes: generating an i.sup.th iteratively reconstructed image by
performing an i.sup.th iterative reconstruction operation in
iterative reconstruction on the preset volume of projection data;
and generating an i.sup.th fused image by fusing i.sup.th
iteratively reconstructed image and the first image, and displaying
the i.sup.th fused image, wherein i is 1, 2, . . . , m-1, m being a
total number of iterative reconstruction operations in the
iterative reconstruction, and m being an integer greater than or
equal to 2; generating an m.sup.th iteratively reconstructed image
by performing an m.sup.th iterative reconstruction operation in the
iterative reconstruction on the preset volume of projection data,
and displaying the m.sup.th iteratively reconstructed image.
[0009] Optionally, generating the i.sup.th fused image by fusing
the i.sup.th iteratively reconstructed image and the first image
includes: determining a weight of a pixel value in the i.sup.th
iteratively reconstructed image and a weight of a pixel value in
the first image according to a number i of iterative reconstruction
operations; and generating the i.sup.th fused image by fusing the
i.sup.th iteratively reconstructed image and the first image
according to the weight of the pixel value in the i.sup.th
iteratively reconstructed image and the weight of the pixel value
in the first image.
[0010] Optionally, displaying the i.sup.th iteratively
reconstructed image includes displaying the i.sup.th iteratively
reconstructed image and progress information of generating the
m.sup.th iteratively reconstructed image.
[0011] Optionally, displaying the second image includes displaying
the second image and quality information of the second image,
wherein the quality information is indicative of image quality of
the second image relative to the first image.
[0012] According to a second aspect, a low-dose imaging apparatus
is provided. The apparatus includes: an acquiring module,
configured to continuously acquire projection data; a first
processing module, configured to generate a first image by
processing the acquired projection data before a data volume of the
acquired projection data reaches a preset volume, and display the
first image; and a second processing module, configured to generate
a second image by processing the preset volume of projection data
when the data volume of the acquired projection data reaches the
preset volume, and display the second image.
[0013] Optionally, the second processing module is configured to
generate an i.sup.th iteratively reconstructed image by performing
an i.sup.th iterative reconstruction operation in iterative
reconstruction on the preset volume of projection data; and display
the i.sup.th iteratively reconstructed image; wherein i is 1, 2, .
. . , m, m being the total number of iterative reconstruction
operations in the iterative reconstruction, and m being an integer
greater than or equal to 1.
[0014] Optionally, the second processing module is configured to
display the i.sup.th iteratively reconstructed image and progress
information of generating an m.sup.th iteratively reconstructed
image.
[0015] Optionally, the second processing module is configured to:
generate an i.sup.th iteratively reconstructed image by performing
an i.sup.th iterative reconstruction operation in iterative
reconstruction on the preset volume of projection data; and
generate an i.sup.th fused image by fusing i.sup.th iteratively
reconstructed image and the first image, and displaying the
i.sup.th fused image, wherein i is 1, 2, . . . , m-1, m being a
total number of iterative reconstruction operations in the
iterative reconstruction, and m being an integer greater than or
equal to 2; generate an m.sup.th iteratively reconstructed image by
performing an m.sup.th iterative reconstruction operation in the
iterative reconstruction on the preset volume of projection data,
and displaying the m.sup.th iteratively reconstructed image.
[0016] Optionally, the second processing module is configured to
determine a weight of a pixel value in the i.sup.th iteratively
reconstructed image and a weight of a pixel value in the first
image according to a number i of iterative reconstruction
operations; and generate the i.sup.th fused image by fusing the
i.sup.th iteratively reconstructed image and the first image
according to the weight of the pixel value in the i.sup.th
iteratively reconstructed image and the weight of the pixel value
in the first image.
[0017] Optionally, the second processing module is configured to
display the i.sup.th fused image and progress information of
generating the m.sup.th iteratively reconstructed image.
[0018] Optionally, the second processing module is configured to
display the second image and quality information of the second
image, wherein the quality information is indicative of image
quality of the second image compared with the first image.
[0019] According to a third aspect, a low-dose imaging apparatus is
provided. The apparatus includes: a memory, a processor, and a
computer program stored in the memory and executable on the
processor, wherein the computer program, when executed by the
processor, causes the processor to perform steps in the method
according to the first aspect.
[0020] According to a fourth aspect, a non-volatile
computer-readable storage medium is provided. The computer-readable
storage medium stores a computer program, wherein the computer
program, when executed by a processor, causes the processor to
perform steps in the method according to the first aspect.
[0021] According to a fifth aspect, a computer program product is
provided. The computer program product stores instructions, wherein
the instructions, when executed by a computer, causes the computer
to perform the low-dose imaging method according to the first
aspect.
[0022] According to a sixth aspect, a chip is provided. The chip
includes a programmable logic circuit and/or program instructions,
wherein the chip, when executed, is caused to perform the low-dose
imaging method according to the first aspect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] In order to describe the technical solutions in the
embodiments of the present disclosure more clearly, the following
briefly introduces the accompanying drawings required for
describing the embodiments. Apparently, the accompanying drawings
as described below show merely some embodiments of the present
disclosure, and a person of ordinary skill in the art may also
derive other drawings from these accompanying drawings without
creative efforts.
[0024] FIG. 1 is a flowchart of a low-dose imaging method according
to an embodiment of the present disclosure;
[0025] FIG. 2 is a flowchart of generating and displaying a first
image according to an embodiment of the present disclosure;
[0026] FIG. 3 is a flowchart of generating an analytically
reconstructed image according to an embodiment of the present
disclosure;
[0027] FIG. 4 is a flowchart of generating and displaying a second
image according to an embodiment of the present disclosure;
[0028] FIG. 5 is flowchart of generating and displaying a second
image according to an embodiment of the present disclosure;
[0029] FIG. 6 is a flowchart of generating a fused image according
to an embodiment of the present disclosure;
[0030] FIG. 7 is a schematic structural diagram of a low-dose
imaging apparatus according to an embodiment of the present
disclosure; and
[0031] FIG. 8 is a schematic structural diagram of another low-dose
imaging device according to an embodiment of the present
disclosure.
DETAILED DESCRIPTION
[0032] For clearer descriptions of the objects, technical
solutions, and advantages of the present disclosure, the
embodiments of the present disclosure are further described in
detail in combination with the accompanying drawings. Apparently,
the described embodiments are merely some rather than all of the
embodiments. All other embodiments obtained by persons of ordinary
skill in the art according to the embodiments of the present
disclosure without creative efforts shall fall within the
protection scope of the present disclosure.
[0033] In the related art, in image reconstruction technology, an
energy wave such as X-ray, positive electron ray and ultrasonic
wave is adopted to irradiate a target area of a patient from
various different directions, data generated by the energy wave
after passing through the target area of the patient is captured to
be as projection data, and the projection data is then calculated
by a specific algorithm to reconstruct a tomographic image
including the target area of the patient. In the field of image
processing, the X-ray CT technology is that X-ray passes through
human tissue (for example, internal organs) from different
directions, data generated by the X rays after passing through the
human tissue is then captured as projection data, and a human
tomographic image is then reconstructed based on the projection
data. Because the excessive X-ray radiation dose has impact on the
health of patients, a low-dose imaging mode relative to a
conventional dose imaging mode is provided for reducing the impact
on the health of a patient.
[0034] Generally, in the conventional dose imaging mode, a human
tomographic image is reconstructed by an analytical reconstruction
method. The analytical reconstruction method, depending on a
continuous signal model, is sensitive to noise and requires
complete projection data. For example, the analytical
reconstruction method may be a Fourier transform method, a filtered
back-projection method or the like. In the low-dose imaging mode, a
human tomographic image is reconstructed by an iterative
reconstruction method. The iterative reconstruction method depends
on a discrete signal model, and in the case of a low
signal-to-noise ratio (the signal-to-noise ratio is usually
relatively low in the low-dose imaging mode) and incomplete
projection data, the human tomographic image with high quality can
be reconstructed by the iterative reconstruction method relative to
the analytical reconstruction method. For example, the iterative
reconstruction method may be an algebra reconstruction technique
(ART), ordered subsets expectation maximization (OSEM), a total
variation algebra reconstruction technique (TV-ART), maximum a
posteriori probability iterative coordinate descent (Maximum A
Posteriori reconstruction, MAP-ICD), or the like.
[0035] In the low-dose imaging mode, due to low X-ray radiation
dose, the quality of each frame of acquired projection data is low.
In order to ensure the quality of a target image eventually
obtained, iterative reconstruction is usually performed on all
frames of projection data after all the frames of projection data
have been acquired, so as to generate and display the target image.
However, in the process, after waiting for a long time, clinical
treatment may only be performed by using an eventual target image.
Further, it is necessary to wait until all frames of projection
data have been acquired to display the target image, and the time
required to display the target image is long, and thus an operator
has to unnecessarily waste time for waiting.
[0036] In the embodiments of the present disclosure, before a data
volume of the acquired projection data reaches a preset volume,
first processing may be performed on the acquired projection data,
such that a first image is generated and displayed; and when the
data volume of the acquired projection data reaches the preset
volume, second processing is performed based on the preset volume
of projection data, such that a second image is generated and
displayed. Compared with the related art, an image can be displayed
without waiting until all frames of projection data have been
acquired, thus, the time required to display the image is
shortened. In this way, abundant reference data is provided for
clinical treatment, such that an operator does not need to
unnecessarily waste time for waiting.
[0037] An embodiment of the present disclosure provides a low-dose
imaging method, applicable to a low-dose imaging apparatus having a
display function in an imaging system. The imaging system may
further include an imaging source (for example, a tube). The
imaging source emits an energy wave and enables the energy wave to
pass through human tissue from different directions. Data generated
by the energy wave after passing through the human tissue is
captured by an imager (for example, a flat panel detector), and the
data is used as projection data. For example, the energy wave may
be X-ray, positive electron ray, ultrasonic wave or the like, which
is not limited in the embodiments of the present disclosure. The
low-dose imaging apparatus acquires the projection data, and
processes and displays the projection data by using the low-dose
imaging method. As shown in FIG. 1, the low-dose imaging method
includes the following steps.
[0038] In step 101, projection data is continuously acquired.
[0039] In step 102, before a data volume of the acquired projection
data reaches a preset volume, a first image is generated by
processing the acquired projection data, and the first image is
displayed.
[0040] In step 103, a second image is generated by processing the
preset volume of projection data when the data volume of the
acquired projection data reaches the preset volume, and the second
image is displayed.
[0041] The foregoing low-dose imaging apparatus may be a computer,
a server, or the like.
[0042] In summary, in the low-dose imaging method according to the
embodiments of the present disclosure, projection data can be
continuously acquired; before the data volume of the acquired
projection data reaches a preset volume, first processing is
performed on the acquired projection data, such that a first image
is generated and displayed; and when the data volume of the
acquired projection data reaches the preset volume, second
processing is performed based on the preset volume of projection
data, such that a second image is generated and displayed. Compared
with the related art, an image can be displayed without waiting
until all frames of projection data have been acquired, thus, the
time required to display the image is shortened.
[0043] In the embodiments of the present disclosure, the first
image and the second image may be various types of images. For
example, the first image may be an analytically reconstructed
image, the second image may be an iteratively reconstructed image,
alternatively, the second image may be an image generated after
image fusion is performed on the first image and the iteratively
reconstructed image. The types of the first image and the second
image are not limited in the embodiments of the present disclosure.
According to the method, the first image and the second image are
generated and displayed during the process of continuous
acquisition of projection data. That is, an image can be displayed
without waiting until all frames of projection data have been
acquired, thus, the time required to display the image is
shortened. In this way, abundant reference data is provided for
clinical treatment, such that an operator does not need to
unnecessarily waste time for waiting.
[0044] Optionally, in the step 2 as shown in FIG. 2, generating the
first image by processing the acquired projection data, and
displaying the first image may include the following steps.
[0045] In step 1021, an analytically reconstructed image is
generated by analytically reconstructing the acquired projection
data.
[0046] In step 1022, the analytically reconstructed image is
displayed.
[0047] It is assumed that the preset volume is 10 frames. Before
the data volume of the acquired projection data reaches 10 frames,
for example, when three frames of projection data are acquired, an
analytically reconstructed image is generated by analytically
reconstructing the three frames of acquired projection data, and
the analytically reconstructed image is displayed.
[0048] Optionally, during the analytical reconstruction of the
acquired projection data, when the acquired projection data does
not need to be denoised, the low-dose imaging apparatus may
directly perform the analytical reconstruction on the acquired
projection data. When the acquired projection data needs to be
denoised, the low-dose imaging apparatus may denoise the acquired
projection data firstly, and then analytically reconstruct the
acquired projection data. Therefore, optionally, as shown in FIG.
3, generating the analytically reconstructed image by analytically
reconstructing the acquired projection data may include the
following steps.
[0049] In step 1021a, processed projection data is acquired by
denoising the acquired projection data.
[0050] In step 1021b, the analytically reconstructed image is
generated by analytically reconstructing the processed projection
data.
[0051] For example, analytically reconstructing the processed
projection data may include: analytically reconstructing the
processed projection data by a Fourier transform method or a
filtered back-projection method.
[0052] After generating the analytically reconstructed image, the
low-dose imaging apparatus can display the analytically
reconstructed image by a display, so as to provide reference data
for clinical treatment. An operator may perform an initial clinical
treatment task such as a coarse registration task in image guidance
according to the analytically reconstructed image, such that the
operator does not need to unnecessarily waste time for waiting.
[0053] In step 103, when the data volume of the acquired projection
data reaches the preset volume, various ways may be available for
generating the second image by processing the preset volume of
projection data, and displaying the second image. In an aspect, the
processing may be iterative reconstruction, and the generated and
displayed second image is an iteratively reconstructed image. In
another aspect, the processing may include iterative reconstruction
and image fusion, and the generated and displayed second image
includes an iteratively reconstructed image and a fused image. Step
103 is described hereinafter by taking the two aspects as an
example.
[0054] Optionally, in an aspect as shown in FIG. 4, step 103 of
generating the second image by processing the preset volume of
projection data, and displaying the second image may include the
following steps.
[0055] In step 1031, an i.sup.th iteratively reconstructed image is
generated by performing an i.sup.th iterative reconstruction
operation in iterative reconstruction on the preset volume of
projection data.
[0056] For example, in this step, the low-dose imaging apparatus
may generate the i.sup.th iteratively reconstructed image by an ART
method, an OSEM method, a TV-ART method or a MAP-ICD method.
[0057] In step 1032, the i.sup.th iteratively reconstructed image
is displayed.
[0058] i is 1, 2, . . . , m, wherein m is the total number of
iterative reconstruction operations in the iterative
reconstruction, and m is an integer greater than or equal to 1.
[0059] It is assumed that the preset volume is 10 frames and the
total number m of iterative reconstruction operations in the
iterative reconstruction is equal to 3, when the low-dose imaging
apparatus has acquired 10 frames of projection data, a first
iteratively reconstructed image is generated by performing a first
iterative reconstruction operation in the iterative reconstruction
on the 10 frames of projection data, and is then displayed. A
second iteratively reconstructed image is generated by performing a
second iterative reconstruction operation in the iterative
reconstruction on the 10 frames of projection data, and is then
displayed. A third iteratively reconstructed image is generated by
performing a third iterative reconstruction operation in the
iterative reconstruction on the 10 frames of projection data, and
is then displayed.
[0060] In the embodiments of the present disclosure, the low-dose
imaging apparatus may display the iteratively reconstructed image,
such that reference data is provided for clinical treatment, and an
operator can fulfill a more detailed clinical treatment task
according to the iteratively reconstructed image.
[0061] In an optional embodiment, step 1032 of displaying the
i.sup.th iteratively reconstructed image may include: displaying
the i.sup.th iteratively reconstructed image and progress
information of generating an m.sup.th iteratively reconstructed
image.
[0062] For example, the progress information of generating the
m.sup.th iteratively reconstructed image may be a time duration
from a generation moment of the i.sup.th iteratively reconstructed
image to a generation moment of the m.sup.th iteratively
reconstructed image.
[0063] It is assumed that the preset volume is 10 frames, and the
total number m of iterative reconstruction operations in the
iterative reconstruction is equal to 3. In this way, i is equal to
1, 2, and 3 sequentially. When the low-dose imaging apparatus has
acquired 10 frames of projection data, the first iterative
reconstruction operation in the iterative reconstruction is
performed on the 10 frames of projection data, the first
iteratively reconstructed image is generated and displayed, and
progress information of generating the third iteratively
reconstructed image is further displayed. The second iterative
reconstruction operation in the iterative reconstruction is
performed on the 10 frames of projection data, the second
iteratively reconstructed image is generated and displayed, and
progress information of generating the third iteratively
reconstructed image is further displayed. The third iterative
reconstruction operation in the iterative reconstruction is
performed on the 10 frames of projection data, the third
iteratively reconstructed image is generated and displayed, and
progress information of generating the third iteratively
reconstructed image is further displayed.
[0064] In the embodiments of the present disclosure, the low-dose
imaging apparatus displays the i.sup.th iteratively reconstructed
image and the progress information of generating the m.sup.th
iteratively reconstructed image, such that an operator can
understand the generation progress of the iteratively reconstructed
image in time, which facilitates fulfillment of a corresponding
clinical treatment task.
[0065] In another aspect as shown in FIG. 5, step 103 of generating
the second image by processing the preset volume of projection
data, and displaying the second image may include the following
steps.
[0066] In step 1033, an i.sup.th iteratively reconstructed image is
generated by performing an i.sup.th iterative reconstruction
operation in iterative reconstruction on the preset volume of
projection data.
[0067] In step 1034, an i.sup.th fused image is generated by fusing
the i.sup.th iteratively reconstructed image and the first image,
and then displayed.
[0068] i is 1, 2, . . . , m-1, wherein m is the total number of
iterative reconstruction operations in the iterative
reconstruction, and m is an integer greater than or equal to 2.
[0069] In step 1035, an m.sup.th iteratively reconstructed image is
generated by performing an m.sup.th iterative reconstruction
operation in the iterative reconstruction on the preset volume of
projection data, and is then displayed.
[0070] It is assumed that the preset volume is 10 frames, and the
total number m of iterative reconstruction operations in the
iterative reconstruction is equal to 3, and i is equal to 1 and 2
sequentially. When the low-dose imaging apparatus has acquired 10
frames of projection data, a first iteratively reconstructed image
is generated by performing a first iterative reconstruction
operation in the iterative reconstruction on the 10 frames of
projection data, and a first fused image is generated by fusing the
first iteratively reconstructed image and the first image and is
then displayed. A second iteratively reconstructed image is
generated by performing a second iterative reconstruction operation
in the iterative reconstruction on the 10 frames of projection
data, and a second fused image is generated by fusing the second
iteratively reconstructed image and the first image and is then
displayed. The low-dose imaging apparatus generates a third
iteratively reconstructed image by performing a third iterative
reconstruction operation in the iterative reconstruction on the 10
frames of projection data, and then displays the third iteratively
reconstructed image.
[0071] In the embodiments of the present disclosure, the low-dose
imaging apparatus may display the fused image and the m.sup.th
iteratively reconstructed image, such that reference data is
provided for clinical treatment, and an operator may fulfill a
corresponding clinical treatment task according to the fused image
and the m.sup.th iteratively reconstructed image.
[0072] For example, the first image for image fusion may be an
analytically reconstructed image. As the analytically reconstructed
image has higher noise and higher edge information quality, and the
iteratively reconstructed image has lower noise and lower edge
information quality, in the embodiments of the present disclosure,
the low-dose imaging apparatus may generate the i.sup.th fused
image with lower noise and higher edge information quality by
fusing the i.sup.th iteratively reconstructed image and the
analytically reconstructed image generated in step 1021.
[0073] It is assumed that the preset volume is six frames, and the
total number m of iterative reconstruction operations in the
iterative reconstruction is equal to 3, and i is equal to 1 and 2
sequentially. When three frames of projection data have been
acquired, the low-dose imaging apparatus performs analytical
reconstruction on the three frames of projection data, and
generates an analytically reconstructed image J. When six frames of
projection data have been acquired, the low-dose imaging apparatus
generates a first iteratively reconstructed image D1 by performing
a first iterative reconstruction operation on the six frames of
projection data, and further generates a first fused image B1 by
fusing the iteratively reconstructed image D1 and the analytically
reconstructed image and displays the first fused image B1. The
low-dose imaging apparatus generates a second iteratively
reconstructed image D2 by performing a second iterative
reconstruction operation on the six frames of projection data, and
further generates a second fused image B2 by fusing the second
iteratively reconstructed image D2 and the analytically
reconstructed image J and displays the second fused image B2. The
low-dose imaging apparatus then generates a third iteratively
reconstructed image D3 by performing a third iterative
reconstruction operation on the six frames of projection data and
displays the third iteratively reconstructed image D3. In this way,
the low-dose imaging apparatus displays a total of two fused images
B1 and B2 and one iteratively reconstructed image D3.
[0074] In an optional embodiment, step 1034 of displaying the
i.sup.th fused image may include: displaying the i.sup.th fused
image and progress information of generating the m.sup.th
iteratively reconstructed image.
[0075] For example, the progress information of generating the
m.sup.th iteratively reconstructed image may be a time length from
a generation moment of the i.sup.th fused image to a generation
moment of the m.sup.th iteratively reconstructed image.
[0076] It is assumed that the preset volume is 10 frames, the total
number m of iterative reconstruction operations in the iterative
reconstruction is equal to 3, and i is equal to 1 and 2
sequentially. When the low-dose imaging apparatus has acquired 10
frames of projection data, a first fused image is generated and
displayed, and progress information of generating the third
iteratively reconstructed image from the first fused image are
further displayed. The low-dose imaging apparatus generates and
displays a second fused image, and displays progress information of
generating the third iteratively reconstructed image from the
second fused image.
[0077] In the embodiments of the present disclosure, the low-dose
imaging apparatus displays the i.sup.th fused image and the
progress information of generating the m.sup.th iteratively
reconstructed image, such that an operator can understand a
generation progress of a fused image in time, which facilitates
fulfillment of a corresponding clinical treatment task.
[0078] Optionally, as shown in FIG. 6, step 1034 of generating the
i.sup.th fused image by fusing the i.sup.th iteratively
reconstructed image and the first image may include the following
steps:
[0079] In step 1034a, a weight of a pixel value (or a pixel) in the
i.sup.th iteratively reconstructed image and a weight of a pixel
value in the first image are determined according to the number i
of iterative reconstruction operations.
[0080] In step 1034b, the i.sup.th fused image is generated by
fusing the i.sup.th iteratively reconstructed image and the first
image according to the weight of the pixel value in the i.sup.th
iteratively reconstructed image and the weight of the pixel value
in the first image.
[0081] A sum of the weight of the pixel in the i.sup.th iteratively
reconstructed image and the weight of the pixel that is in the
first image and is to be fused with the pixel is 1. In addition,
the weight of the pixel value in the i.sup.th iteratively
reconstructed image is positively correlated to the number i of
iterative reconstruction operations, the weight of the pixel value
in the first image is negatively correlated to the number i of
iterative reconstruction operations. That is, when the number i of
iterative reconstruction operations is larger, the weight of the
pixel value in the i.sup.th iteratively reconstructed image is
larger, and the weight of the pixel value in the first image is
smaller. Generally, the pixel in the image may be a pixel
corresponding to soft tissue or a pixel corresponding to bone
tissue. However, the weight of the pixel value corresponding to
soft tissue in the image and the weight of the pixel value
corresponding to bone tissue may have different increase or
decrease rates and/or modes.
[0082] In the embodiments of the present disclosure, when the
number i of iterative reconstruction operations increases, the
low-dose imaging apparatus may increase the weight of the pixel
value in the corresponding i.sup.th iteratively reconstructed
image, including the weight of the pixel value of the pixel
corresponding to soft tissue and the weight of the pixel value of
the pixel corresponding to bone tissue. However, the weight of the
pixel value of the pixel corresponding to bone tissue and the
weight of the pixel value of the pixel corresponding to soft tissue
have different increase rates and/or modes. Herein, especially, the
weight of the pixel value of the pixel corresponding to bone tissue
is increased. In addition, the weight of the pixel value in the
first image is reduced, including the weight of the pixel value of
the pixel corresponding to soft tissue and the weight of the pixel
value of the pixel corresponding to bone tissue. However, the
weight of the pixel value of the pixel corresponding to bone tissue
and the weight of a pixel value of the pixel corresponding to soft
tissue have different decrease rates and/or modes. When the number
i of iterative reconstruction operations increases to a preset
value, the pixel value in the i.sup.th fused image is equal to the
pixel value in the i.sup.th iteratively reconstructed image. For
example, the preset value may be m-1.
[0083] For example, when the number i of iterative reconstruction
operations is equal to 1, the weight of the pixel value in the
first iteratively reconstructed image is q1, and the weight of the
pixel value in the first image is p1. When the number i of
iterative reconstruction operations is equal to 2, the weight of
the pixel value in the second iteratively reconstructed image is q2
and the weight of the pixel value in the first image is p2, wherein
q1<q2, and p1>p2.
[0084] Optionally, step 103 of displaying the second image may
include: displaying the second image and quality information of the
second image, wherein the quality information is indicative of
image quality of the second image relative to the first image.
[0085] In the embodiments of the present disclosure, in addition to
displaying the second image, the low-dose imaging apparatus may
further display the quality information of the second image, and
the low-dose imaging apparatus may determine the quality
information of the second image by an image quality assessment. In
this way, an operator can understand the quality of the second
image in time, and further determine a clinical treatment task for
which the second image may be used in clinical treatment, such that
the operator does not need to unnecessarily waste time for
waiting.
[0086] Optionally, the image quality assessment may be an objective
assessment of digital image quality. For example, the objective
assessment of digital image quality may be a full reference (FR)
type, a reduced reference (RR) type or a no reference (NR) type. In
the FR, an original image is known, and the quality of a current
image is assessed based on the original image. In the NR, no
original image is present, the quality of the entire image is
predicted based on a local feature of a discernible image in a
current image. The RR is a manner between the FR and the NR. In the
RR, the quality of a current image is assessed by using partial
information of the original image. The original image is the first
image in the embodiments of the present disclosure, and the current
image is the second image in the embodiments of the present
disclosure. For example, the first image may be an analytically
reconstructed image, and the second image may be an iteratively
reconstructed image.
[0087] Alternatively, the second image may be a fused image.
[0088] In addition, the image quality assessment manner may be
alternatively a subjective test assessment manner. In the
subjective test assessment manner, two images are provided to a
viewer under a particular condition (an image source, a display, a
viewing condition or the like). The two images are the second image
and the first image in the embodiments of the present disclosure.
The viewer identifies a large amount of score data according to the
second image and the first image, and acquires statistics of the
large amount of score data, to further obtain the quality
information of the second image. For example, the score data may
include data such as average values and standard deviations. In the
subjective test assessment manner, the quality information of the
second image may have two representation forms. One representation
form is an absolute score representation form, that is, the
absolute quality of the second image is represented. The other
representation form is a difference value representation form, that
is, an absolute difference between assessment results of the second
image and the first image is represented.
[0089] It needs to be noted that the sequence of the steps in the
low-dose imaging method according to the embodiments of the present
disclosure may be appropriately adjusted, and the steps of the
low-dose imaging method may be added or reduced as required. Any
variant method that may be readily figured out by a person skilled
in the art within the technical scope disclosed in the present
disclosure shall fall within the protection scope of the present
disclosure. Therefore, details are not described again.
[0090] In summary, in the low-dose imaging method according to the
embodiments of the present disclosure, projection data can be
continuously acquired; before the data volume of the acquired
projection data reaches a preset volume, first processing is
performed on the acquired projection data, such that a first image
is generated and displayed; and when the data volume of the
acquired projection data reaches the preset volume, second
processing is performed based on the preset volume of projection
data, such that a second image is generated and displayed. Further,
progress information of the second image and quality information of
the second image can further be displayed. Compared with the
related art, an image can be displayed without waiting until all
frames of projection data have been acquired, thus, the time
required to display the image is shortened, and reference data is
provided for clinical treatment.
[0091] An embodiment of the present disclosure provides a low-dose
imaging apparatus. The low-dose imaging apparatus has a display
function and is disposed in an imaging system.
[0092] As shown in FIG. 7, the apparatus 700 includes: an acquiring
module 710, configured to acquire projection data continuously; a
first processing module 720, configured to generate a first image
by processing the acquired projection data before a data volume of
the acquired projection data reaches a preset volume, and display
the first image; and a second processing module 730, configured to
generate a second image by processing on the preset volume of
projection data when the data volume of the acquired projection
data reaches the preset volume, and display the second image.
[0093] In summary, in the low-dose imaging apparatus according to
the embodiments of the present disclosure, the acquisition module
continuously acquires projection data; the first processing module
performs first processing on the acquired projection data before
the data volume of the acquired projection data reaches a preset
volume, such that a first image is generated and displayed; and the
second processing module performs second processing on the preset
volume of projection data when the data volume of the acquired
projection data reaches the preset volume, such that a second image
is generated and displayed. Compared with the related art, an image
can be displayed without waiting until all frames of projection
data have been acquired. Thus, the time required to display the
image is shortened.
[0094] Optionally, the first processing module 720 is configured to
generate an analytically reconstructed image by analytically
reconstructing the acquired projection data; and display the
analytically reconstructed image.
[0095] Optionally, the second processing module 730 is configured
to generate an i.sup.th iteratively reconstructed image by
performing an i.sup.th iterative reconstruction operation in
iterative reconstruction on the preset volume of projection data;
and display the i.sup.th iteratively reconstructed image; wherein i
is 1, 2, . . . , m, m being the total number of iterative
reconstruction operations in the iterative reconstruction, and m
being an integer greater than or equal to 1.
[0096] Optionally, the second processing module 730 is configured
to display the i.sup.th iteratively reconstructed image and
progress information of generating an m.sup.th iteratively
reconstructed image.
[0097] Optionally, the second processing module 730 is configured
to: generate an i.sup.th iteratively reconstructed image by
performing an i.sup.th iterative reconstruction operation in
iterative reconstruction on the preset volume of projection data;
generate an i.sup.th fused image by fusing the i.sup.th iteratively
reconstructed image and the first image, and display the i.sup.th
fused image, wherein i is 1, 2, . . . , m-1, m being the total
number of iterative reconstruction operations in the iterative
reconstruction, and m being an integer greater than or equal to 2;
and generate an m.sup.th iteratively reconstructed image by
performing an m.sup.th iterative reconstruction operation in the
iterative reconstruction on the preset volume of projection data,
and display the m.sup.th iteratively reconstructed image.
[0098] Optionally, the second processing module 730 is configured
to determine a weight of a pixel value in the i.sup.th iteratively
reconstructed image and a weight of a pixel value in the first
image according to a number i of iterative reconstruction
operations; and generate the i.sup.th fused image by fusing the
i.sup.th iteratively reconstructed image and the first image
according to the weight of a pixel value in the i.sup.th
iteratively reconstructed image and the weight of a pixel value in
the first image.
[0099] Optionally, the second processing module 730 is configured
to display the i.sup.th fused image and progress information of
generating the m.sup.th iteratively reconstructed image.
[0100] Optionally, the second processing module 730 is configured
to display the second image and quality information of the second
image, wherein the quality information is indicative of image
quality of the second image relative to the first image.
[0101] In summary, in the low-dose imaging apparatus according to
the embodiments of the present disclosure, the acquisition module
continuously acquires projection data; the first processing module
performs first processing on the acquired projection data before
the data volume of the acquired projection data reaches a preset
volume, such that a first image is generated and displayed; and the
second processing module performs second processing on the preset
volume of projection data when the data volume of the acquired
projection data reaches the preset volume, such that a second image
is generated and displayed. Compared with the related art, an image
can be displayed without waiting until all frames of projection
data have been acquired. Thus, the time required to display the
image is shortened.
[0102] It may be clearly understood by a person skilled in the art
that, for the purpose of convenient and brief description, the
detailed working process of the foregoing apparatuses and modules
may refer to a corresponding process in the foregoing method
embodiments, and details are not described herein again.
[0103] An embodiment of the present disclosure further provides a
low-dose imaging device. As shown in FIG. 8, the device includes: a
memory 801, a processor 802, and a computer program 8011 stored in
the memory 801 and executable on the processor 802, wherein the
computer program 8011, when executed by the processor 802, causes
the processor 802 to perform steps in the low-dose imaging method
according to the foregoing embodiments.
[0104] In summary, in the low-dose imaging apparatus according to
the embodiments of the present disclosure, projection data can be
continuously acquired; before the data volume of the acquired
projection data reaches a preset volume, the acquired projection
data is processed such that a first image is generated and
displayed; and when the data volume of the acquired projection data
reaches the preset volume, the preset volume of projection data is
processed such that a second image is generated and displayed.
Further, progress information of the second image and quality
information of the second image can be displayed. Compared with the
related art, an image can be displayed without waiting until all
frames of projection data have been acquired. Thus, the time
required to display the image is shortened, and reference data is
provided for clinical treatment.
[0105] An embodiment of the present disclosure further provides a
computer-readable storage medium. The storage medium is a
non-volatile readable storage medium, and the computer-readable
storage medium stores a computer program, wherein the computer
program, when executed by a processor, causes the processor to
perform the steps in the low-dose imaging method according to the
foregoing embodiments.
[0106] An embodiment of the present disclosure further provides a
computer program product. The computer program product stores
instructions, wherein the instructions, when executed by a
computer, causes the computer to perform the steps in the low-dose
imaging method according to the foregoing embodiments.
[0107] An embodiment of the present disclosure further provides a
chip. The chip includes a programmable logic circuit and/or program
instructions, wherein the chip, when executed, is caused to perform
the steps in the low-dose imaging method according to the foregoing
embodiments.
[0108] A person of ordinary skill in the art may understand that
all or some of the steps of the embodiments may be implemented by
hardware or a program instructing relevant hardware. The program
may be stored in a computer-readable storage medium. The storage
medium may be a read-only memory, a magnetic disk, an optical disk,
or the like.
[0109] Described above are merely example embodiments of the
present disclosure but are not used to limit the present
disclosure. Any changes, equivalent replacements, and improvements
made within the spirit and principle of the present disclosure
shall fall within the protection scope of the present
disclosure.
* * * * *